Blackboard-eraser.



No. 789,162. PATENTED MAY 9, 1905,

Y W. H. LONDERGON.

BLAGKBOARD ERASER.

APPLIOATION FILED JUNE 20, 1904.

' NTTED STATES Patented May 9, 1905.

PATENT Trice.

BLACKBOARD-ERASER.

SPECIFICATION forming part of Letters Patent No. 789,162, dated May 9, 1905.

Application filed June 20, 190 Serial No. 213,223.

To all whom/ it harry concern:

Be it known that LW'ILLIAM H. LoNDEReoN, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois. have invented certain new and useful Improvements in Blackboard-Erasers, of which the following is a specification.

The object of this invention is to construct a blackboard eraser embodying simplicity and great utility in use and which will be clustless in operation; and the invention consists in the features of construction and combinations of parts hereinafter described and claimed.

In the drawings, Figure 1 is an elevation showing one of the rubbing faces or sides of the eraser; Fig. 2, a side elevation of the eraser; Fig. 3, a cross-section through the center longitudinally, showing the method of securing the strips constituting the eraser one to the other; Fig. 4, an elevation showing an eraser having the body made of a continuous strip, and Fig. 5 a crosssection through the eraser of Fig. t.

The eraser is made of any suitable material possessing rigidity and having the necessary qualifications for rubbing out the marks, and for general use thick felt is preferred.

The feltor other material of which the eraser is made is cut into strips of a width for the depth of eraser desired and of varying lengths to suit the length of eraser, the lengths of the strips varying, so that one strip can be Wrapped around another strip in forming the eraser as a whole. The construction shown employs three strips, of which a is the inner strip, Z) the intermediate strip, and 0 the outer strip. The strip a is folded on itself and its ends brought together, and the intermediate strip b is folded around the inner strip a and its ends brought together, the abutting ends of the strip a being adjacent to the solid portion of the strip 7) and the abutting ends of the strip Z) being adjacent to the solid portion of the strip a, and the outer strip 0 is wrapped around the intermediate strip Z) and its ends brought together, the abutting ends of the strip 0 being adjacent to the solid portion of the strip 5, while the solid portion of the strip cis adjacent to the abutting ends of the strip 6, with the result that the abutting ends of the various means d, so that the several sections are joined v at their center longitudinally and crosswise,

leaving the body of the several strips on each side of the stitching perfectly free to give and take with the use of the eraser, and at the same time the elasticity and firmness of the rubber as a whole is left intact, making the eraser very effective in operation. The line of stitching in the construction shown is covered by a tape or band a, encircling the exterior of the eraser centrally of its depth, so that the stitching is protected by the band and a finished appearance is given to the exterior of the eraser, and at the same time the band furnishes a grip for the fingers and thumb in use and does not interfere with the rubbing qualities of the acting faces of the eraser.

The eraser of the present invention furnishes a rubbing or acting face on both of the edge sides of the body, and this acting face, owing to the central line of stitching, leaves the edges of the various strips free, so as to form dustspaces in use in which the dust will enter, with the result that in operation the eraser is dustless. The ends of the eraser are on a curve, presenting a curved edge face on each side at each end, which can be used effectively for careful erasing of a portion of the marks, and the full edge face on each side presents a rubbing-surface, which can be used elfectively for full erasing of the marks on the blackboard or other appliance with which it is customary or possible to use an eraser. The acting face is made up of the edges of the strips on both sides of the eraser, and these strips, each having a narrow acting edge, form a rubbing-face made up of narrow sections, but forming as a whole a wide rubbing or erasing surface. The edge of each strip is free to give and take independently, making the acting face one having a plurality of spaces for the reception of the dust, so as to render the operation of erasing dustless. The strips at their adjoining or abutting end edges are held in place and supported by the solid portions of the adjacent strip, with the result that a continuous erasing-face having dust-spaces is formed. The eraser is capable of use with either face and can be used until worn to a degree where it is practically impossible tobe held by the hand of the operator, thus giving longevity to the eraser. The ends and sides present sharp corners, which can be used where but little erasing is wanted, and the eraser can be used broad face on or end face on or turned for the edges only to be operative. These various advantages found in the eraser of the present invention add utility, effectiveness, and ease of manipulation in use.

The benefits and advantages of having acting faces composed of the edges of the strip can be attained by a strip of thick material and a strip of thin material wound on each other, as shown in Figs. 4 and 5. The strip of thick material f is wound on itself and on the strip of thin material 9, so that the side edges of the strip of thick material are presented and form the erasing faces or surfaces on both sides of the eraser, as in the construction of Figs. 1, 2, and 3. The strips of thick and thin material are united on a central longitudinal line crosswise of the body of the eraser by being stitched through with thread or other stitching means cl, as in the construction of Figs. 1, 2, and 3, and when thus united the eraser of Figs. 4 and 5 presents, in effect,

a plurality of strips having the feature of elasticity and firmness and which can give and take with the use of the eraser and also fur nishing dust-spaces between the rows of thick material into which the dust will enter. The thick material f at one end can be skived off to present a narrow face it for giving a more finished appearance to the eraser, and the strip of narrow material Q can be used as an outer band for the sections or divisions of the thick material.

What I regard as new, and desire to secure by Letters Patent, is-- 1. A blackboard-eraser having a plurality of layers of semirigid self-sustainable erasive material and having the layers set edgewise and wrapped around each other, and means for holding the layers apart to form dust receiving and retaining spaces between the layers, substantially as described.

2. A blackboard-eraser having a plurality of layers of semirigid self-sustainable material and having the layers set edgewise and wrapped around each other presentingstraight sides and semicircular ends, and means for holding the layers apart to form dust receiving and retaining spaces, substantially as described.

3. A blackboard-eraser havinga plurality of layers of semirigid self-sustainable erasive material and having the layers set edgewise and wrapped around each other and cross-stitched together longitudinally at the center, and means for holding the layers apart and forming dust receiving and retaining spaces between the layers, substantially as described.

I A. A blackboard-eraser havinga plurality of layers of semirigid self-sustainable erasive material, and having the layers set edgewise and wrapped around each other and cross-stitched together longitudinally at the center,means for holding the layers apart and forming dust receiving and retaining spaces between the layers, and a central band encircling the exterior of the body of the eraser, substantially as described.

WILLIAM H. LON DERGON.

Witnesses:

OSCAR W. BOND, WALKER BANNING. 

